sponge crab

Definition of sponge crab

1: a female crab bearing an egg mass

2: any of several crabs commonly found in association with sponges: such asa(1):grass crab(2): a crab of the group Dromiacea that decorates its back with sponges or ascidiansb: any of several hermit crabs of the Pacific coast of North America that excavate their homes in a living sponge (Suberites latus)